The Acura ARX-06 LMDh Race Car Has a 2.4-Liter 10,000-RPM V-6

The final piece of the 2023 LMDh puzzle is here. Acura finally showed off its new prototype race car, the ARX-06 without camouflage on Wednesday and like all of its LMDh counterparts, it's a stunner. The coolest part? How about its 10,000-rpm (!) 2.4-liter twin-turbo V-6?

For a quick refresher, LMDh is a joint creation by IMSA and the ACO, governing body of the 24 Hours of Le Mans. It's an evolution of IMSA's current DPi prototype class—in which Acura races the ARX-05—with an LMP2-derived chassis coming from one of a handful of specified suppliers, and engine and bodywork from an automaker. LMDh adds a spec hybrid system consisting of batteries from Williams Advanced Engineering, motor-generator unit (MGU) and control electronics from Bosch, and a transaxle from XTrac.

Engine regulations are fairly relaxed in LMDh, with dimensions and weight specified, a noise limit of 110 decibels, and a rev limit of 10,000 rpm. The engine doesn't need to be based on a production car unit, and Acura is taking advantage of the freedom allowed with a bespoke engine designed by Honda Performance Development (HPD). Called the AR24e, the engine uses an unusual 90-degree vee-angle to help keep the center of gravity low, and HPD says its 2.4-liter displacement makes it the smallest engine its ever built for endurance racing. (Honda's IndyCar V-6 displaces 2.2 liters, per the series regulations.)